"It's so much money that people spend with the best intentions for buying gifts, and unfortunately not all of those gifts find a loving home," he told AAP.

"So we're seeing increasingly people are choosing to sell those gifts rather than hiding them in a cupboard and gathering dust."

In the second year of Gumtree's annual Christmas survey, Mr Thomas said one million more people will head online this year to sell items via classifieds websites.

In 2011, 16.7 million unwanted gifts were received, and Mr Thomas said the decrease could be accounted for by people spending more sensibly.

"Maybe people are getting smarter with what they give - a lot of people are giving gift cards or donating to charity and you're giving a bit of goodwill, which is quite a nice way of doing it," he said.

Mr Thomas noted that 27 per cent of survey respondents were actually hoping to receive gifts they didn't like so they could make money online.

Considering the average unwanted gift was worth about $65, and 18 per cent of people had sold an unwanted item for $100 or more, it was no surprise that more people were heading online this year to convert unwanted gifts to cash, he said.

A NOTE ABOUT RELEVANT ADVERTISING: We collect information about the content (including ads) you use across this site and use it to make both advertising and content more relevant to you on our network and other sites.